Yes, Backblaze B2 Cloud Storage is fully compatible with Linux. In fact, we expect a significant percentage of our customers to use B2 from Linux.
Our B2 Command Line Tool runs on Linux as well. You can learn more about it here: https://www.backblaze.com/b2/docs/quick_command_line.html.
More projects and products that run on Linux are introducing B2 support. A full list can be found on our integration page.